Adenovirus-Mediated Gene Transfer for Cystic Fibrosis: Safety of Single Administration In the Lung 
SCIENTIFIC ABSTRACT OF THE PROTOCOL 
Practical development of gene transfer for cystic fibrosis will likely necessitate aerosol delivery to the lung. This protocol 
seeks to address two key questions regarding the use of adenovirus vectors for CF gene therapy, can adenovirus 
vectors be administered safely to the lung at dose levels believed to be required for effective correction of the CF defect, 
and is aerosolization of vector a safe mode of administration? The current protocol is an extension of two earlier 
protocols for administration of replication-defective adenovirus vectors (Ad2/CFTR-1 or Ad2/CFTR-2) to the nasal 
and/or sinus respiratory epithelium of CF patients. In the first protocol (ORDA protocol #9212-036), Ad2/CFTR-1 was 
applied to the nasal epithelium of four CF patients. In all four cases changes in electrolyte transport were detected 
following treatment with vector. No adverse effects that could be attributed to the adenovirus vector were detected. 
The second protocol (ORDA protocol #9312-067), which is ongoing, is designed to address two key questions regarding 
the use of adenovirus vectors for CF gene therapy, is it safe to administer virus multiple times, and is it possible to 
obtain evidence of clinical and biochemical efficacy? This protocol is in its early stages, making it premature to make 
definitive conclusions about the eventual outcome. However, no results have yet been obtained from the study that 
would suggest that repeat dosing of adenovirus vectors is unsafe. 
The proposed protocol will use the same second generation adenovirus vector, named Ad2/CFTR-2, that was used in 
the second protocol (#9312-067). This type 2 adenovirus lacks El and in its place contains a modified transcription unit 
with the phosphoglycerate kinase (PGK) promoter and a poly A addition site flanking the CFTR cDNA. Results from 
several studies indicate that PGK promoter will direct modest CFTR expression levels and that it will not be subject to 
inactivation. The E4 region of the vector has also been modified in that the whole coding sequence has been removed 
and replaced by ORF6, the only E4 gene essential for growth of Ad2 in tissue culture. The genome of Ad2/CFTR-2 is 
101% the size of wild type Ad2 and it can be grown readily to high titer in culture. 
Clinical lots of vector are produced using master or working cell bank cells and master virus seed stocks each of which 
has been subjected to rigorous testing. Vector preparations must pass a series of tests before they are released for 
clinical use. 
This study will evaluate the safety of the administration of Ad2/CFTR-2 to the pulmonary airway of patients with CF. 
There will be 8 study groups of 5 patients each, with each patient within a group receiving the same dose of 
Ad2/CFTR-2. The study treatment doses range from 8 x 10 6 to 2.5 x 10 10 IU and increase from the lowest dose to the 
highest dose in half log increments. Three patients will receive the virus by bronchoscopic administration to a lobe of 
the lung. After a 1 month monitoring period and If no adverse effect is noted, 3 patients from the next higher dose group 
will receive the virus through bronchoscopic administration. After an a d ditional 1 month monitor i n g p eriod B pationt s 
freffl-&e J fiithl doeo group wil l recei vo aorocol adro mi atration to the e nti re lun gr A total of f ef ty pationtc with mild to 
m od o rate -dt o easfrjwl l bo onroll ce Hrr the-study. Each study patient will be at 90% or more of their peak pulmonary 
function achieved within the last year. Prior to administration of the vims, study patients will be monitored for at least 3 
weeks to ensure that they are clinically stable. Specifically, the patient will not have experienced a CF exacerbation 
requiring hospitalization or shown evidence of adenoviral shedding within 3 weeks and will not have had an upper 
respiratory infection within 2 weeks prior to treatment with Ad2/CFTR-2. 
Each patient will be closely monitored for 28 days post treatment, 3 days as an inpatient, with discharge on Day 4, and 
24 days as an outpatient. Each patient will be assessed for evidence of an adverse systemic, immune, inflammatory or 
respiratory response to Ad2/CFTR-2. Subsequently, patients will be monitored on a monthly basis for 6 months and 
then at least every 3 months for 1 year. Long-term follow-up by annual query will continue for at least 10 years. Patient 
specimens will also be examined throughout the study for any evidence of Ad2/CFTR-2 viral shedding. 
At post treatment Day 7 of the study, each patient will undergo bronchoscopy. For patients receiving bronchoscopic, 
lobar administration, bronchial alveolar lavage (BAL) will be performed on segments of the Ad2/CFTR-2-treated lobe 
and also contralateral, untreated lobes. Specimens from each BAL will be examined for evidence of an inflammatory or 
immune response. For patients receiving aerosolized treatment, a brushing rather than BAL will be performed. 
Specimens from the brushing will be evaluated for gene expression by RNA template-specific PCR (RS-PCR). 
The outcome of this protocol will add further to our knowledge of the safety and efficacy of adenovirus vectors and will 
be invaluable in the design of subsequent protocols targeted to the respiratory airways and of future generations of 
adenovirus vector. 
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Recombinant DNA Research, Volume 20 
